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PROPOSED RISK MANAGEMENT APPROACH
for
1,4-Benzenediol
(Hydroquinone)
Chemical Abstract Service (CAS) Registry Number:
123-31-9
Environment Canada
Health Canada
July 2008
Proposed Risk Management Approach for Hydroquinone
Government of Canada
Table of Contents
1. ISSUE
1.1 CATEGORIZATION AND THE CHALLENGE TO INDUSTRY AND OTHER INTERESTED STAKEHOLDERS
1.2 FINAL SCREENING ASSESSMENT REPORT CONCLUSION FOR HYDROQUINONE
1.3 PROPOSED MEASURE
2. BACKGROUND
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2.1 SUBSTANCE INFORMATION
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3. WHY WE NEED ACTION
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3.1 CHARACTERIZATION OF RISK
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4. CURRENT USES AND INDUSTRIAL SECTORS
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5. PRESENCE IN THE CANADIAN ENVIRONMENT AND EXPOSURE SOURCES
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5.1 RELEASES TO THE ENVIRONMENT
5.2 EXPOSURE SOURCES
6. OVERVIEW OF EXISTING ACTIONS
6.1 EXISTING CANADIAN RISK MANAGEMENT
6.2 EXISTING INTERNATIONAL RISK MANAGEMENT
7. CONSIDERATIONS
7.1 ALTERNATIVE CHEMICALS OR SUBSTITUTES
7.2 ALTERNATIVE TECHNOLOGIES AND/OR TECHNIQUES
7.3 SOCIO-ECONOMIC CONSIDERATIONS
7.4 CHILDREN’S EXPOSURE
8. PROPOSED OBJECTIVES
8.1 ENVIRONMENTAL OR HUMAN HEALTH OBJECTIVE
8.2 RISK MANAGEMENT OBJECTIVE
9. PROPOSED RISK MANAGEMENT
9.1 PROPOSED RISK MANAGEMENT INSTRUMENT
9.1.1 FUTURE USES
9.1.2 INDUSTRIAL USE SECTOR
9.1.3 ADHESIVES SECTOR
9.1.4 PHOTOGRAPHIC SECTOR
9.1.5 PEST CONTROL PRODUCTS
9.1.6 FOODS AND BEVERAGES
9.1.7 NATURAL HEALTH PRODUCTS
9.1.8 COSMETICS SECTOR
9.2 IMPLEMENTATION PLAN
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10. CONSULTATION APPROACH
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11. NEXT STEPS / PROPOSED TIMELINE
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12. REFERENCES
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
This proposed risk management approach document builds on the previously released risk
management scope document for 1,4-benzenediol, and outlines the proposed control actions for
this substance. Stakeholders are invited to submit comments on the content of this proposed risk
management approach or provide other information that would help to inform decision making.
Following this consultation period, the Government of Canada will initiate the development of
the specific risk management instrument(s) where necessary. Comments received on the
proposed risk management approach will be taken into consideration in developing the
instrument(s). Consultation will also take place as instrument(s) are developed.
1. ISSUE
1.1 Categorization and the Challenge to Industry and Other Interested Stakeholders
The Canadian Environmental Protection Act, 1999 (CEPA 1999) (Canada 1999) requires the
Minister of the Environment and the Minister of Health (the Ministers) to categorize all
substances on the Domestic Substances List (DSL). Categorization involves identifying those
substances on the DSL that a) are considered to be persistent (P) and/or bioaccumulative (B),
based on the criteria set out in the Persistence and Bioaccumulation Regulations, and “inherently
toxic” (iT) to humans or other organisms, or b) present, to individuals in Canada, the greatest
potential for exposure (GPE). In addition, the Act requires the Ministers to conduct screening
assessments of substances that meet the categorization criteria. The assessment further
determines whether the substance meets the definition of “toxic” set out in section 64 of
CEPA 1999.
In December 2006, the Challenge identified 193 chemical substances through categorization
which became high priorities for assessment due to their hazardous properties and their potential
to pose risks to human health and the environment. In February 2007, the Ministers began
publishing, for industry and stakeholder comment, profiles of batches containing 15 to 30
high-priority substances. New batches are released for comment every three months.
In addition, the mandatory information–gathering provisions under section 71 of CEPA 1999 are
being used under the Challenge to gather specific information where it is required. The
information that is collected through the Challenge will be used to make informed decisions and
appropriately manage any risks that may be associated with these substances.
The substance 1,4-benzenediol, Chemical Abstract Service (CAS) Registry Number 123-31-9,
referred to throughout this document by “hydroquinone,” was included in Batch 1 of the
Challenge under the Chemicals Management Plan.
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
1.2 Final Screening Assessment Report Conclusion for Hydroquinone
A Notice summarizing the scientific considerations of a final screening assessment report was
published by Environment Canada and Health Canada in the Canada Gazette, Part I, for
hydroquinone on July 5, 2008, under subsection 77(6) of CEPA 1999. The final screening
assessment report concluded that hydroquinone is entering or may be entering the environment in
a quantity or a concentration or under conditions that constitute or may constitute a danger in
Canada to human life or health.
On the basis of the carcinogenicity of hydroquinone, for which there may be a probability of
harm at any level of exposure as well as the potential inadequacy of the margin between
estimated exposure from products and the critical effect level for non-cancer effects, it is
concluded that hydroquinone is a substance that may be entering the environment in a quantity
or concentration or under conditions that constitute or may constitute a danger in Canada to
human life or health (Canada 2008).
Based on the available information, it is concluded that hydroquinone is not entering the
environment in a quantity or concentration or under conditions that have or may have an
immediate or long-term harmful effect on the environment or its biological diversity, or that
constitute or may constitute a danger to the environment on which life depends. It is therefore
concluded that hydroquinone does not meet the criteria in paragraph 64a and 64b of CEPA 1999,
but that it does meet the criteria in paragraph 64c of CEPA 1999.
The final screening assessment report also concluded that hydroquinone does not meet the
criteria for persistence and does not meet the criteria for bioaccumulation, as defined by the
Persistence and Bioaccumulation Regulations (Canada 2000) made under CEPA 1999. The
presence of hydroquinone in the environment does not result primarily from human activity.
For further information on the final screening assessment report conclusion for hydroquinone,
refer to the final screening assessment report, available at
http://www.chemicalsubstanceschimiques.gc.ca/challenge-defi/batch-lot_1_e.html.
1.3 Proposed Measure
Following a screening assessment of a substance under section 74 of CEPA 1999, a substance
may be found to meet the criteria under section 64 of CEPA 1999. The Ministers can propose to
take no further action with respect to the substance, add the substance to the Priority Substances
List (PSL) for further assessment, or recommend the addition of the substance to the List of
Toxic Substances in Schedule 1 of CEPA 1999. Under certain circumstances, the Ministers must
make a specific proposal either to recommend addition to the List of Toxic Substances or to
recommend the implementation of virtual elimination (or both). In this case, the Ministers
proposed to recommend the addition of hydroquinone to the List of Toxic Substances in
Schedule 1 of CEPA 1999. As a result, the Ministers will develop a regulation or instrument
respecting preventive or control actions to protect the health of Canadians and the environment
from the potential effects of exposure to this substance.
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
The final screening assessment report did not conclude that hydroquinone meets the conditions
set out in subsection 77(4) of CEPA 1999. As a result, hydroquinone will not be subject to the
virtual elimination provisions under CEPA 1999 and will be managed using a life-cycle
approach, to prevent or minimize its release into the environment.
2. BACKGROUND
2.1 Substance Information
Hydroquinone is part of the chemical grouping discrete organics and the chemical sub-grouping
phenols.
Table 1 presents other names, trade names, chemical groupings, the chemical formula, the
chemical structure and the molecular mass for hydroquinone.
Table 1. Identity of Hydroquinone
CAS Registry Number
DSL name
Inventory names1
Other names
Chemical group
Chemical sub-group
Chemical formula
123-31-9
1,4-Benzenediol
1,4-Benzenediol (TSCA, DSL, ENCS, AICS, ECL,
SWISS, PICCS, ASIA-PAC, NZIoC)
Hydroquinone (DSL, EINECS, PICCS)
Hydrochinon (EINECS, SWISS, PICCS)
Benzene, 1,4-dihydroxy- (PICCS)
P-dihydroxybenzene (PICCS)
P-hydroxyphenol (PICCS)
Hydroquinone; 1,4-Benzoquinol; 1,4-Dihydroxybenzene;
4-Hydroxyphenol; Aida; Arctuvin; Benzohydroquinone;
Benzoquinol; Black & White Bleaching Cream; BQ(H);
Diak 5; Dihydroquinone; Eldopacque; Eldopaque;
Eldopaque Forte; Eldoquin; Eldoquin Forte; HE 5;
Hydroquinol; NSC 9247; p-Benzenediol;
p-Dihydroquinone; p-Dioxybenzene; p-Hydroquinone;
p-Phenylenediol; p-Quinol; Phiaquin; Quinol; Solaquin
Forte; Tecquinol; Tenox HQ; UN 2662; UN 2662 (DOT)
Discrete organics
Phenols
C6H6O2
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
Chemical structure
HO
SMILES
Molecular mass
1
OH
Oc(ccc(O)c1)c1
110.11 g/mol
From NCI 2007: AICS (Australian Inventory of Chemical Substances); ECL (Korean Existing Chemicals List);
EINECS (European Inventory of Existing Chemical Substances); ELINCS (European List of Notified Chemical
Substances); ENCS (Japanese Existing and New Chemical Substances); PICCS (Philippine Inventory of
Chemicals and Chemical Substances); TSCA (Toxic Substances Control Act Chemical Substance Inventory);
ASIA-PAC (Combined Inventories from the Asia-Pacific Region); NZIoC (The New Zealand Inventory of
Chemicals).
3. WHY WE NEED ACTION
3.1 Characterization of Risk
Based principally on the assessment of the European Commission, a critical effect for
characterization of risk to human health is carcinogenicity, for which a mode of induction
involving direct interaction with genetic material cannot be precluded.
With respect to non-cancer effects, the lowest oral no-observed-effect level (NOEL)
(15 mg/kg-bw/day) is from the rat 2-generation reproduction study, based on parental toxicity.
However, given that the predominant source of exposure to the general population is through the
naturally occurring presence of hydroquinone in foods and beverages, derivation of a margin of
exposure between effect levels in dietary studies with experimental animals and upper-bounding
estimates of exposure would not be meaningful. For non-cancer effects, the incremental
exposure and risk associated with hydroquinone in environmental media resulting from its
manufacturing and industrial uses are considered to be negligible.
Dermal exposure to hydroquinone from use of consumer products can occur. The consumer
product scenario with the highest potential dermal exposure is contact with oxidative hair dye
containing hydroquinone (7.5 x 10-3 µg/kg-bw/day). There is a margin of exposure of well over
1 000 000 between this value and the dermal no-observed-adverse-effects level (NOAEL) of
73.9 mg/kg-bw/day in the 90-day rat study. With respect to non-cancer effects via the dermal
route, this margin is considered adequate to account for uncertainty in the database on exposure
and effects (Canada 2008).
Risks associated with skin-lightening preparations containing hydroquinone, regulated under the
Food and Drugs Act, need to be considered together with the clinical benefits of the
preparations, a task which is beyond the scope of this screening assessment. However, Health
Canada has received 10 reports (between January 1, 1965 and November 30, 2007) of adverse
reactions suspected to be associated with the use of over-the-counter skin-lightening creams
(Personal communication from Jenna Griffiths, Marketed Health Products Directorate, Health
Products and Food Branch, Health Canada, January 8, 2008; unreferenced).
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
4. CURRENT USES AND INDUSTRIAL SECTORS
According to the submissions made under section 71 of CEPA 1999, the known current uses of
hydroquinone in Canada include the following: as a polymerization inhibitor in unsaturated
polyester and methylmethacrylate resin monomers; as a stabilizer in colorants and various types
of industrial and consumer adhesives, thread lockers and thread sealants; as an additive to heat
shrink tubing, restorative paste, bonding tape, film tape, liquid bandages, etc; as a performance
additive in sheetfed printing and heatset inks; and as a reducing agent in photographic
developing solutions (Canada 2007).
A number of other uses of hydroquinone in Canada have also been identified. Although
prohibited for use in cosmetic products applied to the skin and mucous membranes, including
skin-lightening products (Health Canada 2007a), there were 110 notifications of cosmetic
products containing hydroquinone filed with Health Canada under the Cosmetic Regulations of
the Food and Drugs Act, primarily in manicure preparations and hair dyes, at concentrations
ranging up to 3% (Health Canada 2007b). Health Canada’s Drug Product Database lists 34
marketed products. This does not included products that are not marketed, discontinued or have
been inactivated. Hydroquinone is also found in 3 licensed natural health products (NHPs),
which were all previously DIN-assigned products (now discontinued DINs).
Provincially, the National Association of Pharmacy Regulatory Authorities (NAPRA) lists
hydroquinone topical preparations as Schedule II drugs, which are less strictly regulated and do
not require a prescription but do require professional intervention from the pharmacist at the
point of sale and possibly referral to a practitioner. They are available only from the pharmacist
and must be kept within an area of the pharmacy where there is no public access and no
opportunity for patient self-selection (www.napra.ca) (Personal communication from Robin
Marles, Natural Health Products Directorate, Health Products and Food Branch, Health Canada,
November 22, 2007; unreferenced).
Hydroquinone is also present at 0.3% concentration as a stabilizer in two pest control products
registered under the Pest Control Products Act. One product is a restricted-class herbicide for
use in irrigation canals to control vegetation and the second product is a commercial-class
microbiocide used in oil field water injection recovery systems (PMRA 2007).
Hydroquinone may also be used as a chemical intermediate in the synthesis of the following
types of chemicals: antioxidants and antiozonants used in rubber processing; antioxidants used in
industrial fats, oils and foods; and stabilizers for paints, varnishes, motor oils and fuels. It is used
in the photographic industry for the development of black-and-white film and hospital X-rays
and also in lithography. It has also been reported as a component of casting compounds, and may
be used as a corrosion inhibitor in boilers and cooling towers (OECD SIDS 2002).
5. PRESENCE IN THE CANADIAN ENVIRONMENT AND EXPOSURE SOURCES
5.1 Releases to the Environment
Anthropogenic releases of hydroquinone may occur during its production and use in
photographic applications, antioxidants, monomer inhibitors, dyes and pigments, agricultural
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
chemicals and as a stabilizer in paints and varnishes, motor fuels and oils. It may also be released
to the environment in the effluent of photographic processes (HSDB 2006). Table 2 summarizes
on-site releases and off-site disposal of hydroquinone (and its salts) to unspecified media from
industrial facilities in Canada from 2001 to 2006, as reported in the National Pollutant Release
Inventory (NPRI 2007).
Table 2. Releases of hydroquinone for 2001–2006
Year
2006
2005
2004
2003
2002
2001
On-site
releases
2
2
2
2
0
1
Off-site
disposal
0
1
49
1
1
1
Release
units
kg
kg
kg
kg
kg
kg
According to the submissions made under section 71 of CEPA 1999, three Canadian companies
reported releases of hydroquinone (whether alone, in a product, in a mixture or in a
manufactured item) totaling 103 kg in the 2006 calendar year (Canada 2007).
5.2 Exposure Sources
Hydroquinone occurs naturally as a conjugate with beta-D-glucopyranoside in the leaves, bark
and fruit of a number of plants, especially the ericaceous shrubs such as cranberry, cowberry,
bearberry and blueberry (Varagnat 1982; Harbison and Belly 1982; Hudnall 1987). It has been
detected at low levels in coffee, tea, red wine, beer, cola soft drinks, 2% milk, orange juice, corn,
wheat and rice cereals, wheat germ, and various fruits, including pears, oranges, cantaloupes,
cherries, asparagus, apples, blueberries and cranberries (Deisinger et al. 1996). Hydroquinone is
known to play a role in the defence mechanisms of certain classes of beetles (Aneshansley et al.
1969). It is also known to be present in the particulate fraction of cigarette smoke (IARC 1985).
Hydroquinone is manufactured by the oxidation of aniline to quinone and the subsequent
reduction of quinone to hydroquinone. Other routes of synthesis include the oxidative cleavage
of diisopropyl benzene and the hydroxylation of phenol (OECD SIDS 2002). According to
current information reported pursuant to the CEPA 1999 section 71 notice with respect to
hydroquinone, 17 Canadian companies and 2 foreign companies reported importing
hydroquinone (whether alone, in a product, in a mixture or in a manufactured item) in 2006 in a
quantity greater than or equal to 100 kg, while another 10 Canadian companies reported
importing hydroquinone (whether alone, in a product, in a mixture or in a manufactured item) in
2006 in a quantity less than 100 kg. No Canadian companies manufactured hydroquinone in
Canada in 2006 (Canada 2007b). The total quantity imported was between 100 000 kg and
1 000 000 kg (Canada 2007b).
Upper-bounding estimates of hydroquinone intake for each age group in the general population
of Canada are based upon maximum identified concentrations in environmental media and food
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
items (Canada 2008). The upper-bounding estimate of exposure to hydroquinone for the general
population ranges from 91.32 µg/kg-bw (kilogram of body weight) per day for the 60+ age group
to 393.45 µg/kg-bw per day in the 0–6 month (not formula-fed) age group. Based on these
estimates, intake from food and beverages represents the predominant source of exposure to
hydroquinone for the general population of Canada, comprising over 99% of total exposure for
all age groups. As indicated earlier, hydroquinone and its glucose conjugate,
4-hydroxyphenyl-β-D-glucopyranoside (arbutin), are naturally present in many foods and
beverages. Since arbutin is reported to hydrolyze readily in dilute acidic solutions to yield
D-glucose and hydroquinone, ingested arbutin is expected to be converted to free hydroquinone
in the stomach (Deisinger et al. 1996). As such, both measured concentrations of hydroquinone
and arbutin in food and beverages were considered in deriving estimates of intake from food and
beverages. Contributions to total intake from other media (ambient and indoor air, water and
soil) were considered to be negligible in comparison to intake from food and beverages.
Dermal exposure during the use of consumer products containing hydroquinone can also
contribute to total exposure for the general population. A number of upper-bounding exposure
scenarios for different products containing hydroquinone have been generated (Canada 2008).
These include intake from the use of black-and-white photographic developing solutions
(7.9 x 10-4 µg/kg-bw/day), household adhesives (7.2 x 10-5 µg/kg-bw/day), manicure
preparations (3.0 x 10-4 µg/kg-bw/day) and oxidative hair dyes (7.5 x 10-2 µg/kg-bw/day).
Because of the low vapour pressure of hydroquinone, it is considered unlikely that there will be
any significant inhalation exposure associated with any of these uses. With regard to exposure
resulting from the use of photographic developing solutions, the results from a recent study
involving the biological monitoring of professional darkroom workers in the United Kingdom
indicated no increase in the urinary excretion of hydroquinone for exposed workers, indicating
that even for this potentially highly exposed population, intake of hydroquinone from use of
developing solutions is unlikely to be a concern (UKHSE 1993).
Exposure estimates were not derived for skin-lightening preparations containing hydroquinone,
regulated under the Food and Drugs Act, due to the wide range of potential clinical uses.
Additionally, access to these products is controlled through provisions established by the
National Association of Pharmacy Regulatory Authorities.
Hydroquinone is known to be present in the particulate fraction of cigarette smoke (IARC 1985)
and this may also contribute to overall exposure.
Confidence in the upper-bounding estimate of intake of hydroquinone in environmental media is
considered to be moderate, as limited measured concentrations were available. Confidence in the
estimates of exposure estimates from use of consumer products containing hydroquinone is
considered to be low, as the estimates are based on assumptions; the estimates of exposure
resulting from these uses, however, are considered to be overestimates of actual exposure.
6. OVERVIEW OF EXISTING ACTIONS
6.1 Existing Canadian Risk Management
Hydroquinone is subject to
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
- reporting under the National Pollutant Release Inventory;
- the Food and Drug Regulations or the Natural Health Products Regulations under the Food
and Drugs Act, when used in drugs or natural health products, respectively;
- the Drug Product Database, in which it is registered as an active ingredient;
- the Controlled Products Regulations established under the Hazardous Products Act, requiring
any ingredient on the Ingredient Disclosure List to be disclosed on the Material Safety Data
Sheet;
- the Consumer Chemicals and Containers Regulations, 2001 established under the Hazardous
Products Act, requiring products to be classified against criteria based on short-term exposure
situations, with the results determining the appropriate product labelling and packaging
requirements;
- the Cosmetic Ingredient Hotlist established under the Food and Drugs Act;
- the Tobacco Reporting Regulations and the Determination of Phenolic Compounds in Tobacco
Smoke; and
- the Pest Management Regulatory Agency (PMRA) List of Formulants (List 1).
6.2 Existing International Risk Management
Hydroquinone is listed on the U.S. Toxic Substances Control Act (TSCA) inventory.
Hydroquinone is designated as a hazardous air pollutant (HAP) by the U.S. Environmental
Protection Agency (EPA). It is listed under the U.S. Superfund Amendments and Reauthorization
Act (SARA) as well as the Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA). It is listed on the U.S. Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) as a List 1 inert ingredient. Hydroquinone is also listed under the U.S. Food and Drug
Administration (FDA) Federal Food, Drug, and Cosmetic Act (FD&C Act) as an indirect food
additive. There are currently no international risk management measures in place for
hydroquinone. The Organisation for Economic Co-operation and Development (OECD) has
stated that hydroquinone has a low priority for further work. It is listed by the International
Agency for Research on Cancer (IARC) as a Group 3 carcinogen (inadequate evidence of
carcinogenicity in humans and inadequate or limited evidence in experimental animals).
The U.S. FDA is currently proposing a ban on over-the-counter sales of skin-lightening products
containing hydroquinone. The intention is to restrict them only to prescription use under medical
supervision. The rule has been put out for public comments through Dec. 26, 2006, (Federal
Register 2006).
7. CONSIDERATIONS
7.1 Alternative Chemicals or Substitutes
There are alternative chemicals to the use of hydroquinone for black-and-white photographic
development. However these alternatives may not provide the same desired artistic effects as the
hydroquinone-based developing solutions for particular uses. As this specialized discretionary
market is artistic in nature and highly technical, it is uncertain as to what impact control
measures would have on this community.
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
There are alternative chemistries for hair dyes which do not require hydroquinone.
For certain industrial uses, a major alternative replacement chemical for hydroquinone is
catechol. As catechol is also being managed under the Chemicals Management Plan, it would not
be considered a suitable replacement. Due to the complex nature of some of the industrial uses
for hydroquinone, it is unknown whether there are suitable replacements for all applications.
It is important to note that these substitutes have not undergone an assessment to determine
whether they meet the criteria under section 64 of CEPA 1999.
7.2 Alternative Technologies and/or Techniques
The rise of digital photography, Web publishing and home printing is quickly replacing the home
darkroom for photographers wishing to do custom black-and-white photography in Canada.
However there is a very small segment of the artistic photographic community which
occasionally desires certain effects for black-and-white photographs. These effects are not yet
possible with digital technology and require photodeveloping solution containing hydroquinone.
7.3 Socio-economic Considerations
Where information was available, socio-economic factors have been considered, at least in a
qualitative manner, in the selection process for an instrument respecting preventive or control
actions, and in the development of the risk management objective(s). Socio-economic factors
will also be considered in the development of regulations, instrument(s) and/or tool(s) as
identified in the Cabinet Directive on Streamlining Regulation (Treasury Board of Canada
Secretariat 2007) and the guidance provided in the Treasury Board document Assessing,
Selecting, and Implementing Instruments for Government Action.
As no additional risk management actions are proposed under CEPA, socio-economic
considerations are considered to be negligible.
7.4 Children’s Exposure
In screening assessments, potential exposure of the general population, including infants and
children, is estimated. To the extent possible, based on available data, exposure to hydroquinone
from multiple routes (i.e. inhalation, ingestion and contact on the skin) and possible sources
(ambient air, indoor air, drinking water, food, beverages—including breast milk and formula for
infants)—soil, and in some instances consumer products) is estimated. Infants and children’s
exposure is characterized by their unique physiology (e.g. intake of air, food, and water relative
to body size) and generally known behaviour characteristics (e.g. crawling versus walking,
mouthing activity).
As part of the Challenge, the Government asked industry and interested stakeholders to submit
any information on the substance that may be used to inform risk assessment, risk management
and product stewardship. In particular, stakeholders were asked through a questionnaire if any of
the products containing the substance were intended for use by children. Given the information
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
received, and other data considered, it is proposed that no additional risk management actions to
specifically protect children are required for this substance at this time.
8. PROPOSED OBJECTIVES
8.1 Environmental or Human Health Objective
An environmental or human health objective is a quantitative or qualitative statement of what
should be achieved to address environmental or human health concerns identified during a risk
assessment.
As the primary source of exposure for the general public would be from consuming naturally
occurring hydroquinone in food and beverages, the proposed human health objective for
hydroquinone is to minimize exposure to, and hence risk to human health associated with,
exposure to hydroquinone to the extent practicable from non-naturally occurring sources.
8.2 Risk Management Objective
A risk management objective is a target expected to be achieved for a given substance by the
implementation of risk management tool(s) and/or instrument(s). The proposed risk management
objective is to reduce exposure to hydroquinone.
9. PROPOSED RISK MANAGEMENT
9.1 Proposed Risk Management Instrument
As required by the Government of Canada’s Cabinet Directive on Streamlining Regulation2, and
criteria identified in the Treasury Board document entitled Assessing, Selecting, and
Implementing Instruments for Government Action, the proposed risk management regulations,
instrument(s) and/or tools were selected using a consistent approach, and took into consideration
the information that has been received through the Challenge and other information available at
the time.
In order to achieve the risk management objective and to work towards achieving the human
health objective, the risk management being considered for hydroquinone pertains to a
requirement for notification of the federal government regarding any proposed future uses.
Additional restrictions on the use of hydroquinone in cosmetic products (nail systems and hair
dyes) will be proposed. The government will also be proposing to regulate hydroquinonecontaining health products as a prescription drug rather than available in over-the-counter
products (e.g., skin lightening products)
2
Section 4.4 of the Cabinet Directive on Streamlining Regulation states that “Departments and agencies are to:
identify the appropriate instrument or mix of instruments, including regulatory and non-regulatory measures, and
justify their application before submitting a regulatory proposal”.
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Proposed Risk Management Approach for Hydroquinone
9.1.1
Government of Canada
Future Uses
It is proposed to create a provision whereby any future uses of hydroquinone would be subject to
federal government notification.
9.1.2 Industrial Use Sector
Industrial chemical uses are governed under provincial health and safety regulations and all
workplace chemicals must comply with the Controlled Products Regulations, which includes
Workplace Hazardous Materials Information System (WHMIS) labelling, supply of Material
Safety Data Sheets (MSDS) and worker training. In addition, it is proposed to create a provision
whereby any proposed use of hydroquinone above a specific level in a manufacturing application
would require that the federal government be notified.
9.1.3 Adhesives Sector
The minute concentrations of hydroquinone as currently employed in the adhesives industry in
specialty adhesives are trapped in the cured adhesive matrix and are not readily absorbed through
the skin based on modelled exposure studies (Canada 2008). As there is negligible exposure to
hydroquinone through adhesives, this sector will not be a candidate for risk management of
hydroquinone.
9.1.4 Photographic Sector
Photographic chemicals are used by professional, artistic and hobby photographers and when
purchased at retail, would be required to have appropriate short-term exposure labelling in
accordance with the Consumer Chemicals and Containers Regulations, 2001. This labelling
helps to reduce unintentional short-term incidents, but will have an impact on long-term
exposure as well if the user follows the safety warnings and uses the appropriate protective
equipment. Therefore the Government of Canada considers that the risks posed by hydroquinone
in photographic chemicals are already appropriately regulated under the Hazardous Products
Act.
9.1.5 Pest Control Products
Hydroquinone is used as a formulant stabilizer at concentrations of no greater than 0.3% in an
aquatic herbicide and in a microbiocide for use in oil field water injection recovery systems.
These products are regulated under the Pest Control Products Act and because of their
designations as restricted and commercial class, they are not for sale to the general public. Once
the reassessment document is finalized, hydroquinone will be re-categorized from PMRA List 1
to List 4B for use only in the above-mentioned products. As pest control products are governed
by a previously existing act, this sector will not be a candidate for risk management of
hydroquinone under CEPA 1999.
9.1.6 Foods and Beverages
The screening assessment report for hydroquinone notes that oral intake is the primary route of
exposure for the general population. The primary oral intake source for the general public is
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
from the consumption of foods such as pears, wheat and wheat breads, tea and coffee, rice,
onions, cranberries, blueberries and red wine. Food and beverages are identified as the major
source of exposure to hydroquinone for the general population of Canada, making up over 99%
of the total intake for all age groups. Hydroquinone has also been detected in cigarette smoke
and wood smoke. There is currently no evidence to indicate that the natural occurrence of
hydroquinone in foods poses a risk to Canadian consumers. Fruits and vegetables are known to
contain various naturally occurring substances which have been linked to important health
benefits. Consumers are encouraged to continue to eat fruits and vegetables as recommended in
Canada’s Food Guide.
As hydroquinone is a normal constituent in whole foods and is present in low concentrations,
foods and beverages will not be a candidate for risk management under CEPA 1999.
9.1.7 Natural Health Products
Health Canada will propose to add hydroquinone-containing natural health products at any dose,
except when in natural substances (e.g. plant materials), to Schedule F of the Food and Drug
Regulations, so that they can be regulated as prescription drugs.
9.1.8 Cosmetics Sector
Issues pertaining to hydroquinone in cosmetics fall under the regulatory area of the Food and
Drugs Act. Section 16 of the Act states that no person shall sell a cosmetic product that has in it
any substance that may injure the health of the user when the cosmetic is used according to its
customary method. To help cosmetic manufacturers satisfy this requirement, Health Canada has
developed the Cosmetic Ingredient Hotlist—a list of substances which are restricted and
prohibited in cosmetics. Hydroquinone is on the Hotlist as being prohibited for use in cosmetic
products applied on the skin or mucous membranes. Health Canada will propose further
restrictions on the use of hydroquinone in hair dyes and artificial nail systems through
amendments to the Hotlist.
9.2 Implementation Plan
The proposed instrument will be published in the Canada Gazette, Part I, no later than July
2010, as per the timelines legislated in CEPA 1999.
Releases of hydroquinone will continue to be monitored under the National Pollutant Release
Inventory.
It is expected that it will take approximately 12 months to place hydroquinone on Schedule F of
the Food and Drug Regulations so that it can be regulated as a prescription drug.
10. CONSULTATION APPROACH
The risk management scope for hydroquinone, which summarized the proposed risk management
under consideration at that time, was published on January 19, 2008, and is available at
www.ec.gc.ca/TOXICS/EN/detail.cfm?par_substanceID=236&par_actn=s1. Industry and other
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Proposed Risk Management Approach for Hydroquinone
Government of Canada
interested stakeholders were invited to submit comments on the risk management scope during a
60-day comment period. Comments received on the risk management scope document were
taken into consideration in the development of this proposed risk management approach
document.
Consultation for the risk management approach will involve publication on July 5, 2008, and a
60-day public comment period.
The primary stakeholders include
•
•
the chemical manufacturing industry
the Pest Management Regulatory Agency
11. NEXT STEPS / PROPOSED TIMELINE
Actions
Risk Management Approach published on-line
60-day public comment period
Response to comments on the Risk Management Approach
Consultation on the draft instrument
Publication of the proposed instrument
Formal public comment period on the proposed instrument
Publication of the final instrument
Date
July 5, 2008
July 5, 2008 to Sept. 3, 2008
Winter 2008–2009
Winter 2009–2009
No later than July 2010
No later than July–August
2010
No later than January 2012
Industry and other interested stakeholders are invited to submit comments on the content of this
proposed risk management approach or provide other information that would help to inform
decision making. Please submit comments prior to September 3, 2008, since the Government of
Canada will be moving forward with the risk management of hydroquinone after this date.
Pursuant to section 313 of CEPA 1999, any person who provides information to the Minister
under CEPA 1999 may submit with the information a request that it be treated as confidential.
During the development of the risk management instrument(s) and/or tool(s), there will be
opportunity for consultation on the proposed instrument(s). Comments and information
submissions on the proposed risk management approach should be submitted to the address
provided below:
Existing Substances Division
Place Vincent Massey, 20th Floor
351 Saint Joseph Boulevard
Gatineau QC K1A 0H3
Tel: 1-888-228-0530 / 819-956-9313
Fax: 1-800-410-4314 / 819-953-4936
Email: [email protected]
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Proposed Risk Management Approach for Hydroquinone
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